Detergent manufacturers incorporate enzymes into their laundry detergent products to improve their performance. Examples of such laundry detergent compositions are described in WO98/50513, WO99/09126, WO99/09127, WO00/42157, WO00/42146 and WO01/62885.
Enzymes, being a catalytic detergent ingredient, are preferably incorporated into laundry detergent products to replace existing non-catalytic detergent ingredients. Detergent manufactures seek to formulate their laundry detergent products such that the optimal performance of enzymatic activity is achieved and that allows the reduction in the levels of other detergent ingredients and compaction of the laundry detergent product. Prior to the present invention, there was a long felt need for catalytic technologies, and especially enzymatic systems, that enable the compaction of the surfactant levels, especially in liquid laundry detergent compositions. Such compacted liquid laundry products exhibit improved environmental profiles, improved efficiency in manufacture, transport and shelf storage.
The inventors have found that the incorporation of certain glycosyl hydrolases into laundry detergent compositions, especially liquid laundry detergent compositions, that additionally comprise a specific polymer system enables the laundry detergent manufacturer to reduce the detersive surfactant levels in the laundry detergent composition. These glycosyl hydrolases have enzymatic activity towards both xyloglucan and amorphous cellulose substrates. In addition, these glycosyl hydrolases are selected from GH families 5, 12, 44 or 74. The glycosyl hydrolase (GH) family definition is described in more detail in Biochem J. 1991, v280, 309-316.
Without wishing to be bound by theory, the Inventors believe that the broad substrate specificity of these glycosyl hydrolases provides multiple benefits during the laundering process. The Inventors believe that the specific polymer system exhibits a soil remove and soil suspension profile such that improves the access of certain glycosyl hydrolases to the fabric surface. In addition, the Inventors believe the specific polymer system improves the stability of certain glycosyl hydrolases.
The Inventors believe that these certain glycosyl hydrolases biopolish the fabric surface of key soil binding sites such as amorphous cellulose and residual xyloglucan, leading to a more open fibre pore structure. It is believed that this mechanism provides good cotton soil removal, cotton soil release and whiteness maintenance performance. It is believed that this effect on fibre morphology improves the optical effects of brighteners and hueing technology, when present in the laundry detergent composition. The multiple activities of these enzymes towards cellulose and xyloglucan may also contribute to the robustness of overall soil release/removal benefits achieved compared to conventional enzymes having only cellulase activity.
The Inventors have observed significant improvement in the cotton soil release profile, whiteness maintenance profile and dingy cleaning performance of these glycosyl hydrolases when they are formulated in combination with a specific polymer system. Furthermore, these glycosyl hydrolases exhibit good stability profiles in liquid laundry detergent compositions when formulated in combination with the specific polymer system. The specific polymer system is described in more detail below but preferably the polymer system is at least a dual polymer system comprising two polymers, and is even more preferably at least a ternary polymer system comprising three polymers.